COC polymer compounds for 3D printing

Abstract

Cyclic olefin copolymer (COC) is useful as a build material for 3D printing, especially desktop 3D printing.

Claims

1. A method of using a build material during 3D printing comprising cyclic olefin copolymer having a heat deflection temperature HDT/B ((0.45 MPa) ISO 75, Parts 1 and 2) of 75° C. and an impact modifier, other than cyclic olefin copolymer elastomer, capable of modifying the impact properties of the cyclic olefin copolymer, wherein the impact modifier is selected from the group consisting of styrenic block copolymers, olefinic block copolymer, and combinations of them comprising the step 3D printing the build material.

2. The method of claim 1, wherein the build material further comprises optical brighteners, process aids, rheology modifiers, thermal and UV stabilizers, fluorescent and non-fluorescent dyes and pigments, radio-opaque tracers, conductive additives (both thermal and electrical), inductive heating additives, and non-silicone releases; and combinations of them.

3. The method of claim 1, wherein the styrenic block copolymer is styrene-ethylene/butylene-styrene (SEBS).

4. The method of claim 1, wherein the cyclic olefin copolymer is ethylene-norbornene copolymer which has a CAS No. of 26007-43-2.

5. The method of claim 1, wherein the ethylene-norbornene copolymer has the following structure: ##STR00002## wherein X ranges from about 40 wt. % to about 20 wt. % and wherein Y ranges from about 60 wt. % to about 80 wt. %.

6. The method of claim 1, wherein the cyclic olefin copolymer has a weight average molecular weight (Mw) ranging from about 40,000 to about 130,000.

7. The method of claim 1, wherein the build material is a filament build material.

Description

EXAMPLES

Comparative Examples A-S and Examples 1 & 2

(1) Formulations and Test Results

(2) Table 2 shows the list of ingredients. Table 3 and Table 4 show the extrusion conditions. Tables 5 and 6 show the molding conditions. Tables 7 shows the recipes, which extrusion conditions and which molding conditions were used, and the 3D Printing test results. Only two Examples proved acceptable for 3D Printing among 21 different formulations by conclusions by an expert in 3D printing based on qualitative observations of performance compared to commercially available polymeric filaments used by that expert.

(3) TABLE-US-00002 TABLE 2 Commercial Brand Name Ingredient and Purpose Source Novapol ® GF- LLDPE (linear low density NOVA 0218 polyethylene) Chemicals Topas ® 6017S COC (cyclic olefin copolymer), a clear TOPAS grade with a heat deflection temperature Advanced HDT/B of 170° C. used for parts Polymers, requiring resistance to short-term, high- Inc. temperature exposure. Topas ® 6013S COC (cyclic olefin copolymer) a clear TOPAS grade with a heat deflection temperature Advanced HDT/B of 130° C., a value which Polymers, cannot be attained by many amorphous Inc. polymers and having a combination of high purity, chemical resistance, high transparency and high HDT/B, useful for products such as labware, which can be gamma- and steam-sterilized. Kraton ® G1651 Styrene-ethylene/butylene-styrene Kraton (SEBS) thermoplastic elastomer Performance Polymers, Inc. TIONA ® RCL4 TiO.sub.2 Cristal Global Zeonor ® 1060R Cyclo-olefin polymers (COP) Zeon Corporation Zeonor ® 1020R Cyclo-olefin polymers (COP) Zeon Corporation Irganox ® B225 Processing and long-term thermal BASF stabilizer OCV ™ milled Milled glass fibers Owens fiber 737BC Corning 1/64 Elvaloy ® PTW Ethylene terpolymer DuPont ™ Topas ® 8007S COC (cyclic olefin copolymer) a clear TOPAS grade with a heat deflection temperature Advanced HDT/B of 75° C., being especially Polymers, suited for packaging of Inc. moisture-sensitive products because of its low water absorption and very good barrier properties and having a lower elastic modulus and higher elongation than other Topas COC grades. Topas ® 5013L COC (cyclic olefin copolymer) a clear TOPAS grade with a heat deflection temperature Advanced HDT/B of 130° C. and being Polymers, characterized by high flowability and Inc. excellent optical properties, for applications such as optical parts, e. g., lenses, and optical storage media, where low birefringence and high molding accuracy (pit replication) are essential, as well as for medical and diagnostic applications. TOPAS ® COC (cyclic olefin copolymer) TOPAS ELASTOMER elastomer with good transparency, Advanced E-140 excellent barrier properties and high Polymers, purity and being highly flexible and Inc. having an 89 Shore A hardness, suitable for numerous flexible applications such as medical devices, medical tubing, IV bags, and other healthcare applications

(4) TABLE-US-00003 TABLE 3 Extruder Conditions Extruder Type Prism 16 mm TSE (40 L/D) screw extruder Order of Addition All ingredients mixed together and fed into the extruder hopper. Zone 1 280° C. Zone 2 280° C. Zone 3 280° C. Zone 4 280° C. Zone 5 280° C. Zone 6 280° C. Zone 7 280° C. Zone 8 280° C. Zone 9 280° C. Die 280° C. RPM 300

(5) TABLE-US-00004 TABLE 4 Extruder Conditions Extruder Type Prism 16 mm TSE (40 L/D) screw extruder Order of Addition All ingredients mixed together and fed into the extruder hopper. Zone 1 230° C. Zone 2 230° C. Zone 3 230° C. Zone 4 230° C. Zone 5 230° C. Zone 6 230° C. Zone 7 230° C. Zone 8 230° C. Zone 9 230° C. Die 230° C. RPM 300

(6) TABLE-US-00005 TABLE 5 Molding Conditions Nissei 88 molding machine Drying Conditions before Molding: Temperature (° C.) 80° C. Time (h) 14 hrs Temperatures: Nozzle (° C.) 260 Zone 1 (° C.) 254 Zone 2 (° C.) 249 Zone 3 (° C.) 249 Mold (° C.) 66 Oil Temp (° C.) 30 Speeds: Screw RPM (%) 100 % Shot - Inj Vel Stg 1 70 % Shot - Inj Vel Stg 2 20 % Shot - Inj Vel Stg 3 20 % Shot - Inj Vel Stg 4 20 % Shot - Inj Vel Stg 5 15 Timers: Injection Hold (sec) 4 Cooling Time (sec) 15 Operation Settings: Shot Size (mm) 38-41 Cushion (mm) 0.8-3.3

(7) TABLE-US-00006 TABLE 6 Molding Conditions Nissei 88 molding machine Drying Conditions before Molding: Temperature (° C.) 80° C. Time (h) 14 hrs Temperatures: Nozzle (° C.) 232 Zone 1 (° C.) 226 Zone 2 (° C.) 221 Zone 3 (° C.) 221 Mold (° C.) 54 Oil Temp (° C.) 30 Speeds: Screw RPM (%) 100 % Shot - Inj Vel Stg 1 70 % Shot - Inj Vel Stg 2 20 % Shot - Inj Vel Stg 3 20 % Shot - Inj Vel Stg 4 20 % Shot - Inj Vel Stg 5 15 Timers: Injection Hold (sec) 6 Cooling Time (sec) 20 Operation Settings: Shot Size (mm) 32 Cushion (mm) 5

(8) TABLE-US-00007 TABLE 7 Example A B C D Kraton G1651 23.000 23.000 23.000 23.000 Topas 6013s 53.500 50.000 46.400 43.000 Topas 21.500 20.000 18.600 17.000 6017s TiO.sub.2 RCL 4 2.000 2.000 2.000 2.000 Novapol GF-0218 5.000 10.000 Zeonor 1060R 15.000 Total (%) 100.0 100.0 100.0 100.0 Extrusion Conditions Table 3 Table 3 Table 3 Table 3 Molding Conditions Table 5 Table 5 Table 5 Table 5 3D Printing Performance No Good No Good No Good No Good Example E F G H I J Kraton G1651 23.000 23.000 10.000 23.000 23.000 15.000 Topas 6013s 33.900 48.900 56.900 Topas 6017s 15.000 TiO.sub.2 RCL 4 2.000 2.000 2.000 2.000 2.000 2.000 Zeonor 1020R Zeonor 1060R 49.000 58.900 61.900 Novapol 26.000 16.000 26.000 26.000 26.000 26.000 GF-0218 IRGANOX 0.00 0.100 0.100 0.100 0.100 0.100 B225 Total (%) 100.0 100.0 100.0 100.0 100.0 Extrusion Table 4 Table 4 Table 4 Table 3 Table 3 Table 3 Conditions Molding Table 6 Table 6 Table 6 Table 5 Table 5 Table 5 Conditions 3D Printing No No No No No No Performance Good Good Good Good Good Good Example K L M N O P Kraton G1651 10.000 10.000 10.000 15.000 15.000 15.000 Topas 6013s 46.900 53.900 43.900 TiO.sub.2 RCL 4 2.000 2.000 2.000 2.000 2.000 2.000 Zeonor 1060R 61.900 68.900 58.900 LLDPE 16.000 16.000 16.000 26.000 26.000 26.000 Novapol GF-0218 ANOX BB 0.100 0.100 0.100 0.100 0.100 0.100 011/IRGANOX B225 OCV ™ milled 10.000 10.000 10.000 10.000 fiber 737BC 1/64 Elvaloy PTW 3.000 3.000 3.000 3.000 Total (%) 100.0 100.0 100.0 100.0 100.0 100.0 Extrusion Table 4 Table 4 Table 4 Table 3 Table 3 Table 3 Conditions Molding Table 6 Table 6 Table 6 Table 5 Table 5 Table 5 Conditions 3D Printing No No No No No No Performance Good Good Good Good Good Good Example 1 Q R S 2 Topas 8007 93.000 90.000 95.00 Topas 5013 90.000 85.000 Kraton 5.000 5.00 G1651 TiO.sub.2 RCL 4 2.000 Topas E-140 10.000 10.000 15.000 Total (%) 100.0 100.0 100.0 100.0 100.00 Extrusion Table 3 Table 3 Table 3 Table 3 Table 3 Conditions Molding Table 5 Table 5 Table 5 Table 5 Table 5 Conditions 3D Printing Good No No No Good Performance Good Good Good

(9) Examples 1 and 2 and Comparative Example Q differed from all of Comparative Examples A-P and R and S because Examples 1 and 2 and Comparative Example Q used the Topas COC grade having the lowest heat deflection temperature HDT/B commercially available.

(10) Without being limited to a particular theory, it is possible that such grade is superior in performance as a build material for 3D printing filaments to other Topas grades because Topas 8007 grade is distinguished from other Topas grades by having a heat deflection temperature HDT/B of 75° C. ((0.45 MPa) ISO 75, Parts 1 and 2). The next current commercial grades, both Topas 5013 and Topas 6013, have a heat deflection temperature HDT/B of 130° C.

(11) Though not presently commercially available, without undue experimentation, a person having ordinary skill in the art could replace Topas 8007 grade in Example 1 with a grade having a heat deflection temperature HDT/B of less than 125° C., or 120° C., or 115° C., or 110° C., or 105° C., or 100° C., or 95° C., or 90° C., or 85° C., or 80° C., or any other temperature between 76° C. and 125° C., depending upon which new Topas grades are brought to commercial availability. Experimentation could then identify acceptable performance properties based on the results identified in these Examples and Comparative Examples.

(12) The Comparative Examples using grades of Topas COC other than grade 8007 did not differ significantly in properties other than HDT/B. As the commercial literature from Topas about its COC grades indicate, Grade 8007 does not have (a) the lowest or highest volume flow index as measured according to ISO 1133, either at 260° C. or 115° C.; (b) density; or (c) water absorption. Grade 8007 did have both the lowest water vapor permeability of 0.023 g*mm/m.sup.2*d at 23° C. and 85% relative humidity according to test method DIN 53 122 and mold shrinkage of 0.1-0.5% with testing conditions at 60° C. and a 2 mm wall thickness, using an unidentified test method.

(13) Examples 1 and 2 differ from Comparative Example Q in that Comparative Example Q uses Topas E-140 COC elastomer, whereas Examples 1 and 2 use a styrenic block copolymer, SEBS. The inadequacy of a COC elastomer was surprising because it would be expected that a COC elastomer as an impact modifier would work well for a COC thermoplastic build material for 3D printing. The deficiency of Comparative Example Q was unacceptable warping.

(14) A common deficiency of the Topas grades tested is the defect of warping in the object being 3D printed using those other Topas grades, even with impact modifiers present. Comparative Examples K-S all experienced unacceptable warping during 3D printing. Only Comparative Example Q used Topas 8007 grade, explained above.

(15) Warping is a major problem in 3D printing, arising from a tendency of polymers to shrink as they cool. Integrity of proper 3D printed shape can be lost during 3D printing as a layer shrinks, which causes a distortion of surface for the next layer being printed in the z-axis. The warping can be so severe that the 3D printing head collides with the object being 3D printed. Simply put, surprisingly, Examples 1 and 2 did not warp during 3D printing. That common deficiency of warping by polymers used for 3D printing has been unpredictably overcome by the use of the Topas 8007 grade of COC.

(16) The deficiencies of Comparative Examples A-E were lack of adhesion to the printing surface. The deficiencies of Comparative Examples F-J variously were polymer sticking to the 3D print head nozzle and curling issues. The deficiencies of Comparative Examples K-S were warping during 3D printing.

(17) Examples 1 and 2 resulted in filament which, when 3D printed, had adhesion at the printing surface, no curling or sticking to the 3D print head nozzle, or most of all, no warping.

(18) The invention is not limited to the above embodiments. The claims follow.